Blow dryers have been around for decades. Typical blow dryers include a heating coil and a rotating fan housed within a protective outer shell. When power is supplied to the device, the heating coil responds by heating the air within the apparatus. The heated air is then forcefully expelled out of the device by means of a rotating fan. This results in accelerating the process of removing moisture absorbed within the hair follicle by rapidly heating the temperature of the hair.
Blow dryers tend to fall in the 1000 W to 2000 W range and typically receives power transmitted through a cord that is plugged into a wall outlet, so there is not an urgent design objective to minimize power consumption or waste heat. But, this power output presents challenges to power from a battery. All batteries have a level of internal electrical resistance/impedance, which generates heat during both charging and discharging. Thus, using batteries to power a heating element and fan also generates heat within the batteries, battery packs, or internal circuitry as they discharge. This heat can shorten the life of the batteries, and may affect the discharge rate or run time of the batteries. Excess heat can cause the safety control systems (part of the “battery management system” or BMS) to shut off the battery.
It would be desirable to develop a battery-operated blow dryer that is capable of cooling to batteries and related circuitry to increase their performance, avoid overheating and safety issues, and/or extend the life of the batteries.